graf and m



F. C. GRAF AND M. J. ZWOSTA.

AUTOMATIC TRAIN CONTROL. APPLICATION FILED JULY19,1920.

Patented Apr. 11, 1922.

3 SHEETS-SHEET I.

Arm/mm WITNESSES F. C. GRAF AND M. J. ZWOSTA.

AUTOMATIC TRAINCONTROL.

APPLICATION FILED JULY 19,1920.

3 SHEETSSHEET 2.

'Pamnted Apr. 11, 1922.

auaaaam W .M 1 A In MJZrmsw ATTORNEYS F. C. GRAF AND M. J. ZWOSTA.

AUTOMATIC TRAIN 001111201.

ikPFLICA'l'lON HLED JULY 19,1920.

Patented Apr. 11, 1922.

3 SHEETS-SHEET 3.

UNITED STATES PATENT OFFICE.

FREDERICK C. GRAF, 0F BROOKLYN, AND MICHAEL J'. ZWOSTA, OF NEW YORK, N.Y.

AUTOMATIC TRAIN CONTROL.

Application filed July 19,

To all whom it may concern:

Be it known that we, FREDERICK C. GRAF and 7 MICHAEL J. Zwos'rA, bothcitizens of the United States, and residents, respectively, of the cityof New York, borough of Brookl n, in the county of Kings and State of lew York, and city of New York, borough of Queens, county of Queens, andState of New York, have invented a new and Improved Automatic TrainControl, of which the following is a full, clear, and exact description.

This invention relates to an automatic train control system which isoperable in conjunction with the signal systems now in use or which maybe independently operated by a separate system with equal eificiency.

Various signal systems have been employed satisfactorily where the rulesgoverning their use have been strictly observed by the train operators,but numerous and frequent accidents have occurred by the failure ofoperators to observe the signals.

This invention therefore broadly contemplates the provision of anautomatic train control system which entirely eliminates the failure onpart of the human element and which seeks to conform strictly with there quirements defined by railroad experts as a prerequisite to thepracticability of a device of this character.

The control systems for this purpose which have been heretofore employedlargely include trip devices on the train which are adapted to contactwith ramps or other devices adjacent the track and it is one of thespecific objects of this invention to eliminate the use of means of thischaracter by resorting to means operating in conjunction with the airbrake system which is controlled by normally closed circuit adapted tobe broken should the train attempt to enter an occupied block ahead.

A further object of the invention is to provide an apparatus which is soconstructed that it will perform its intended function if any essentialpart fails or is removed, or it a brake, cross, ground, short circuit orother failure of energy in the electric circuits occurs when in use.

A still further object of the invention is to provide an apparatus orsystem of the character described which will operate under allconditions of speed, weather, wear, oscillation and "shock.

A still further object of the invention is to provide a fool-proofsystem and apparatus Specification of Letters Patent.

Patented Apr. 11, 1922. 1920. Serial No. 397,191.

which will defeat any attempt of an engineer anticipating a closedsignal from passing the same, said apparatus being provided with meanswhich functions to stopthe train immediately upon manipulation of theapparatus with such an intent.

A still further object of the invention is to provide an apparatus whichincludes means which permits the train to pass a closed signal at apredetermined reduced rate of speed.

Another object of the invention is to provide a tram control systemwhich comprises means for automatically closing the throttle or electricswitch as the case may be prior to the application of the brakes.

Another object of the invention is to provide an automatic drain forpreventing accidental application of the brakes due to leakage of theair from the main reservoir pressure to the operating mechanism.

A still further object of the invention is to provide adjustable meanswhereby the ap paratus may be set for either a service or emergencystop.

WVit-h the above recited and other objects in view, some of which willbe apparent hereafter, reference is made to the following detaileddescription, claims and accompanying drawings forming a part of thisapplication, and in which;

Figure 1 is a diagrammatic illustration of the application of theapparatus to a locomotive.

Figure 2 is an enlarged sectional view of a part of the system.

Figure 3 is a detail sectional view of the electrically operated latchtaken approximately on the line 33 of Figure 2.

Figure 4 is a diagrammatic detail view of a speedometer controlledcircuit closer con stituting one of the features of the invention.

Figure 5 is a detailed sectional view of the reset and drain valve.

Figure 6 is a diagrammatic plan view of the block circuits employed inconnection with the invention.

Referring to Figure 6 of the drawings, 10 designates a plurality oftrack blocks, the rails of which are insulated at 11 from each other andwhich are adapted to be normally connected by jumper circuit 12 havingan armature 13 controlled by relay 1%. The relay magnet is normallyenergized through the circuit wires 15 and 16 by the battery 17 and istie-energized only when the block ahead is occupied by a train whichshort. circuits the circuit wires 15 as clearly illustrated in Figure 6of the drawing.

By way of practical illustration as shown in Figure 1 of the drawingsthe rear wheel 20 of the locomotive and the front wheel 21 of the tenderare insulated from. each other except for their engagement with the rail22 and the same are included in the circuit 23. The circuit 23 alsoincludes a battery 24, a-latch magnet 25, a switch 26 and the crossconnection 27 in which is arranged a Speedometer controlled circuitcloser 28. The latch magnet is arranged in a hous ing 29 andnormallyoperates when energized by the battery 24 during the closed condition ofthe circuit 23, to retain the latch 30 in looking position due tothe'engagement of the arm 31 with the latch arm 32. The speedometercontrolled circuit closer 28 included in the cross connection 27comprises a wiper arm 33 which operates over a contact plate 34hereillustrated of a from the valve casing 39.

' cylinder head.

sufficient length whereby the arm 33 will contact therewith upto thetime that the train does not exceed five miles an hour and the purposeof this circuit closer will be hereinatter explained.

Referring to Figure 2 of the drawings, 36 designates one terminal of thebrake pipe line which is normally closed. by a valve 87 having a valvestem 88 extending outwardly The means which is adapted to co-act withthe valve stem 38 to open the valve 37 and bleed the brake pipe lineincludes a cylinder 40 in which is.

mounted a sliding piston 41 having a piston rod 42 extending through oneextremity of the cylinder in alignment with the valve stem 38 andprovided on its free extremity with an abutment head 43. A coiledexpansion spring 44 normally -forces the piston in a direction tomaintain the abutment head 43 out of engagement with the valve stem 38in which position the piston abuts against and effects the seating ofthe exhaust valve 44 with its seat to close the exhaust opening 45 inthe cylinder head 46. The engage ment of the pistonwith the valve andthe valve with its seat serves'to space the piston from the cylinderhead to leave the inlet 47 opento the space between the piston and theThe exhaust opening communicates with a plurality of radial exhaustports 48 formed in the cylinder head and which communicate to theatmosphere. The valve stem 49 ot the exhaust valve 44 is secured to aplunger 50 which operates in an air chamber 51 secured to the cylinderhead. The chamber 51 communicates with the cylinder 40 through a pipe52, the opposite extremities of which are open respectively to thechamber 51 and the cylinder 40 a predetermined distance from thecylinder head designated at'53. A valve cook 54 controls thecommunication between the cylinder 40 and the chamber 51 for a purposeto be hereinafter set forth.

The mechanism for admitting air to the cylinder 40 through the intake47, to operate the piston 41 is controlled by the latch 30 and the sameincludes an actuator 60 which is provided with a spring pressed bolt 61normally engaged by the nose of the latch when the magnet 25 isenergized. The ac tuator 60 is secured to the free end of a plunger rod62 the opposite extremity of which is formed with a head 63 mounted forsliding movement in the cylindrical frame 64; the upper portion of saidframe having an adjustable sleeve 65 through which the plunger rod 62 isadapted to slide. A coiled expansion spring 66 normally. exerts atension between the sleeve 65 and the plunger head 63 whereby uponrelease of the .nose off the latch from the boltv 61 the actuator 60will be moved in a direction to engage the stem 67 ot' a valve 68. Thevalve 68 controls communication between a supply pipe 69 leading fromthe main reservoir and a pipe 70 leading therefrom to the inlet 47 ofthe cylinder 40. The actuator head is guided through the engagement ofthe guide rods '71 in the guides 72 to prevent radial turning movementin order to insure' at all times the proper alignment of the bolt 61with the nose of the latch 30. The actuator head is provided with a lug73 which engages the valve stem 74 0:1 a by-pass valve 75 to effect theunscating of the valve whenthe actuator is in normal locked positionthrough the engageinent ot the bolt (31 with the latch 30. The bypassvalve 75v controls communication between the pipe 76 and the by-passpipe 77, the opposite extremity'ot'said latter pipe communicating withthe'pipe 70. The opposite extremity of the pipe 76 com municates with athree-wayvalve 78, the remaining ports of which communicate with anexhaust or drain nipple 79 anda branch pipe 80 leading to the mainreservoir. The pipe 70 has interposed'therein a needle Valve 82 forregulating the flow of air therefrom to the inlet of the cylinder 40 andis fur-' ther provided with a four-way connection 83 between the pointof entry of the by-pass pipe 7 7 and the needle valve. A discharge pipe84 establishes communication between the tour way connection 83 and thesection of the pipe 7 0 which lies between the needle valve and theinlet 47. A quick exhaust valve 85 is disposed in the discharge pipe 84and is nor mally seated by the pressure or the air entering the pipe 70but is adapted to unseat automatically upon a back pressure from thecvlinder 40. The remaining port Oftll; connection 88 communicates withthe throttle control cylinder 86 through the conduit pipe 87. A piston88 suitably connected with the throttle lever 89 operates in thecylinder 86 to close the throttle upon the entrance of the air pressurethereto through the pipe 87.

In use and operation of the system, when the block ahead of the train isclear, the armature 13 of the jumper circuit is closed by the relaymagnet 14 which is energized through the wiring 15 and 16 fromthe-battery 17. Should the engineer run past a closed signal due to hisfailure to observe or for any other reason, the train in the block aheadwill have short circuited the wiring 15 and 16 thus deenergizing therelay magnet 14 and opening the jumper circuit 12. As the wheels 20 and21 of the train straddle the insulated'section 11 of the track, thecircuit 23 will be broken or ruptured if the train advances at a speedgreater than five miles an hour for the reason that the wiper arm 33will be out of contact with the plate 34. Immediately upon the breakingof the circuit 23, the magnet 25 will be deenergized and the arm 31thrown to a position to permit the latch arm 32 to be released. The noseof the latch 30 will then be free to swing under the tension of thespring 66 thereby permitting said spring to move the actuator head 60which due to its'engagement with the valve stem 67 will unseat the mainvalve 68. This will result in the feeding of the air from the mainreservoir through the pipe 69 to the pipe 70, a part of the pressuretraveling through the pipe 87 to the throttle control cylinder 86 toactuate the throttle lever 89 and effecting a closing of the throttle.The remainder of the air will feed through the needle valve 82 into theinlet 47 of the cylinder 40 between the piston 41 and the cylinder head46. The piston Will be moved against the tension of the spring 44 untilthe abutment head 43 engages with the valve stem 38, resulting in theunseating of the valve 37 and the bleeding of the brake pipeline. Thiswill eflect the application of the brakes to bring the train to a stop.The pressure in the cylinder 40 will be sufficient to maintain theexhaust valve 44 in seated condition and it is assumed that the valvecock 54 is closed for an emergency stop. If a service stop is desired,the valve cook 54 will be open and when the piston 41 uncovers the port53, a portion of the air will flow through the pipe 52 to the chamber 51equalizin the pressure on both sides of the plunger 50 and permittingthe weight of the same to unseat the valve 44 and exhaust the pressurein the cylinder 40 through the port 45 and the ports 48 to theatmosphere. When the pressure is sufliciently reduced the spring 44 willfunction to disengage the abutment head 43 of the valve stem 38 therebyreleasing the brakes intermittently to obtain the service stop.

After the train has been brought to a stop by this system and the blockahead is clear,

means is provided for resettin the system which includes a reset cyliner 9O having a cylinder head 91 provided with an inlet port 92 fromwhich extends a conduit pipe 93 communicating with the pipe 76 at apoint between the three-way valve 78 and the by-pass valve 75. The resetcylinder 90 is carried by the cylindrical frame 64 in alignmenttherewith and the piston 94 operating therein is provided with a pistonrod 95 extending through the closed end of the cylinder into theoperating frame. The piston 94 is normally advanced toward the cylinderhead by means of a coiled expansion spring 96. To reset the system, thethree- Way valve 78 is manipulated to establish communication betweenthe branch pipe 80 and the pipe 76, thereby opening the pressure fromthe main reservoir through the pipe 93 to the reset cylinder 90 betweenthe piston'94 and the piston head 91. The piston 94 under this pressurewill be moved away from the cylinder head 91 and the stem 95 thereofwill engage the plunger head 63, returning the actuator head 60 to itsnormal position where its bolt 61 will be again engaged by the nose ofthe latch 30. This will permit the spring pressed main valve 68 toreseat through the disengagement of the actuator head with the valvestem 67, thereby cutting ofl' communication of the main reservoirpressure with the feed pipe 70 to the cylinder 40. At the same time thelug 73 will engage the valve stem 74 of the by-pass valve 75 lifting thesame from its seat, the air pressure from the main reservoir will thenpass through the pipes 76 and 77 by way of the by-pass valve 7 5 to thefeed pipe 70 retaining the pressure in the cylinder 40 and the brakes inset condition until the three-way valve is again manipulated to cut offcommunication to the pipe 76 from the main reservoir pressure. Thisoperation of the three-way valve then communicates the pipe 76 with theexhaust or drain nipple 79, permitting the air in the cylinder 40 toreturn through the exhaust pipe and quick release valve 85, pipe 77,by-pass valve 7 5, and pipe 76 to disengage the abutment head 43 fromthe brake pipe valve 37. This position of the threeway valve alsofunctions to relieve the reset cylinder 90 of its pressure and at thesame time drain the pipe 70 of any air pressure which might accidentallyleak through the main valve 68.

Should the engineer attempt to pass a closed signal at a higher rate ofspeed than permitted by the speedometer controlled circuit closer 28, bymanipulating the threeway valve to open thevmain reservoir pressure intothe reset cylinder for the purpose of holding the actuator head againstits proper functioning upon breaking of the circuit, the air pressurewill at the same constructed that it will perform its intended functionregardless of whether an essential part is removed or whether thecircuit is broken or shorted.

It is to be understood thatvthe right is reserved to various embodimentsother than those actually disclosed herein, to the fullest extentindicated by the broadest moaning oi? the terms in which the claims areexpressed and by modifications inthe phraseology of the same.

Having thus described our invention, we claim as newand desire to secureby Letters Patent: "a

-1. In an automatic train control system the combination with anair-brake system in; cluding a main reservoir, a brake pipe, and anormallyclosedexhaust valve in the brake pipe, of means for opening saidvalve comprising a, cylinder, a piston arrangedtherein end adapted toco-act with said valve upon movement of the piston, a teed pipecommunicating respectively with the cylinder and the main, reservoir, afeed valve in said feed pipe, an actuator for said feed valve, retainingmeans for holding said actuator in an inactive position, an electriccircuit for controlling said retaining means, a track having insulatedblocks, means for breaking and establishing electrical communicationbetween the blocks respectively by the presence or absence of a train inadvance, said blocks when in communication serving to complete thecontrol circuit and when out of communication to break said circuit.

2. In an automatic train control system, the combination with an airbrake system including a main reservoir, a brake pipe, and a normallyclosed exhaust valve in the brake pipe, of means for opening saidexhaust valve comprising a cylinder, a feed pipe communicatingrespectively with the cylinder and the main-reservoir, a feed valve insaid feed pipe, anactuator for said feed valve, a by-passpipecommunicating at one end with the feed pipe between the feed valveand the cylinder and open at its opposite end to the atmosphere, abypass valve in said by-pass pipe, said by-pass valve being operable bythe actuator when in inactive position, to retain the said lay-passvalve open, retaining means for said actuator for normally locking'thesame in inactive position, an electric circuit for retaining saidcontrolling means, a track having insulated blocks, means for breakingand establishing electrical communication between the blocks,respectively by the presence or absence of a train in advance, saidblocks when in communication serving-to complete the control circuit andwhen out of communication to break the same. v

Shin an automatic train control system, the combination with the airbrake system thereof including a main reservoir, a brake pipe and anormally closed exhaust valve in said brake pipe, of means for openingsaid exhaust valve to eii'ect the application of the ln-ahes, comprisinga cylinder having a piston arranged therein adapted to co-act with saidexhaust valve upon movement of the piston, a :l'eed pipe communicatingrespectively with the cylinder and said main reservoir, a. normallyclosed i eed valve in said;

feed pipe, an actuator for opening said feed valve, retaining means forholding said actuator in inactive osition, means operable by saidactuator wnen in inactive position for opening the feed pipe between thefeed valve and said cylinder,an electric circuit torretaining saidcontrolling means, a track having insulated blocks, means for breakingand establishing electrical communication between the blocks,respectively by the presence of absence of a train in advance, saidblocks when in communication serving to complete the control circuit andwhen out or connnunication to break the same.

42. In an automatic train control system including in combination atrack having insulated blocks, means for breaking or establishingelectrical communication between said blocks by the presence or absenceof a train in advance, of mechanism on each train for throwing oil? thedriving power of the same and simultaneously ei'l'ecting he plication ofthe brakes when the electrical communication between the blocks isbroken comprising an air chamber communicating with the main reservoirof the air brake system, having a piston therein adapted to bleed thebrake pipe, a valve for controlling the supply from the main reservoirto the air chamber, an actuator for operating said valve, means forretaining said actuator in a position to effect the closing-oi saidvalve, pneumatic means for moving said actuator to an inactive position,said pneumatic means having communication with the main reservoir, avalve for controlling communication between the rese voir and saidpneumatic means, means operable by the actuator when in an inactiveposition for draining the connection between the feed valve and the irchamber, a control circuit for said actuator retaining means normallyclosed when electrical communication between the blocks the track isestaliilished.

5. Ellen automatic train control system including inicombination a trackhaving insulated blocks, means for breaking or estahlishing electricalcommunication between said blocks by the presence or absence of a trainin advance, of mechanism on each train for throwing oil the drivingpower of the same and simultaneously eilecting the application of thebrakes when the electrical communication between the blocks is brokencomprising an air chamber communieating with the main reservoir of theair brake system, having a piston therein adapted to bleed the brakepipe, a valve for controlling the supply from the main reservoir to theair chamber, an actuator for operating said valve, means for retainingsaid actuator in a position to efi'ect the closing of said valve,pneumatic means for moving said actuator to an inactive position, saidpneumatic means having communication with the main reservoir, a valvefor controlling communication between the reservoir and said pneumaticmeans, means operable by the actuator when in an inactive position fordraining the connection .between the feed valve and the air chamber, acontrol circuit for said actuator retaining means normally closed whenelectrical communication between the blocks of the track is established,and pneumatic means operable when the feed valve is open for effectingthe movement of the throttle to throw off the power.

6. In an automatic train control system, the combination with anair-brake system including a main reservoir, a brake pipe, and anormally closed exhaust valve in the brake pipe, of means for openingsaid valve comprising a cylinder, a piston arranged therein and adaptedto coact with said valve upon movement of the piston, a feed pipecommunicating respectively with the cylinder and the main reservoir, afeed valve in said feed pipe, an actuator for said feed valve, retainingmeans for holding said actuator in an inactive position, an electriccircuit for controlling said retaining means, a track having insulatedblocks, means for breaking and establishing electrical communicationbetween the blocks respectively by the presence or absence of a train inad vance, said blocks when in communication serving to complete thecontrol. circuit and when out of communication to break said circuit,and means associated with the cylinder for intermittently causing thepiston to coact with the exhaust valve whereby intermittent applicationof the brakes is obtained.

7. In an automatic train control system, the combination with anair-brake system including a main reservoir, a brake pipe, and anormally closed exhaust valve in the brake pipe, of means for openingsaid valve comprising a cylinder, a piston arranged therein and adaptedto coact with said valve upon movement of the piston, a feed pipecommunicating respectively with the cylinder and the main reservoir, afeed valve in said feed pipe, an actuator for said feed valve, retainingmeans for holding said actuator in an inactive position, an electriccircuit for controlling said retaining means, a track having insulatedblocks, means for breaking and establishing electrical communicationbetween the blocks respectively by the presence or absence of a train inadvance, said blocks when in communication serving to complete thecontrol circuit and when out of communication to break said circuit, andmeans associated with the cylinder for intermittently causing the pistonto react with the exhaust valve whereby intermittent application of thebrakes is obtained, said means comprising an air receiving chamberhaving communication with the cylinder a predetermined distance from theair inlet of the feed pipe, a plungcr mounted in the chamber, a checkvalve control exhaust in the cylinder normally closed by the internalpressure, means for cutting off or establishing communication betweenthe cylinder and said chamber, said plunger adapted to coact with thecheck valve upon movement of the piston to uncover the communicationbetween the cylinder and the chamber.

FREDERICK G. GRAF. MICHAEL J; ZVVOSTA.

In the presence of- VALENTINE J. REEDMAN.

